Elevator control system



Sept. 26, 1944.- H. w. WILLIAMS ELEVATOR CONTROL SYSTEM Filed Nov. 4, 1942 5 Sheets-Sheet l 30d l /aor BF/ BF? 35/ B52 54C 33C 32C Sept. 26, 1944.

5 Sheets-Sheet 3 Fi led Nov. 4, 1942 QxPWIIIIIIIIIIIIIIIIIIII QQY I I I I I I I I I IIIIIIIg m v w w i||||I1|rIi1|| 1 1ll,|| LT I IIWTII N$I I I I I I I I I I I I I I I II I a QQN II I I I I I I I I I I I I I I I.I I/IIE ll oO I I I Illllllllliili W JT 4 Na I I I I I I I I I II I I I I I I I I I 5 I T All 3 Mk I I I I I I I I I I I IIINV v/ M I X x 1 n 1 v e 2 l. killlilllxwg I .T

Z 3 w I \N I I I I IIUIU I I I I I mm, l I I I I I I I I I IHI II I Z 3 (R335 WITNESSES:

INVENTOR Harold 14/ h/l/fimg ATTO NEY Sept. 26, 1944,

Filed Nov. 4, 1942 5- Sheets-Sheet 5 WSN Na? llllllllllll ll, i l l l l l l l l iii-N4 G] INVENTOR f/ara/c/ 14/ M///0075.

VlTNffES: @ZKZ Patented Sept. 26, 1944 ELEVATOR CONTROL SYSTEM Harold W. Williams, Nutley, N. J., assignor to Westinghouse Electric Elevator Company,

Jersey City, N. J., a corporation of Illinois Application November 4, 1942, Serial No. 464,435

3 Claims. (Cl. 17-29) My invention relates to elevator control systerns and more particularly to systems of this character which embody push buttons at the landing floors and in the cars for stopping the cars at selected floors.

One problem of passenger elevator service in tall buildings is that of taking care of heavy interfloor traffic. Where interfloor traflic is heavy, it usually results in confusion and irregular operation of the cars because it requires two stops for each interfloor service, whereas incoming and outgoing service require only one stop per service plus a common stop at the terminal. Therefore, the double stopping for interfloor service places a maximum demand on the system .with resultant poor operation.

' One object of my invention is to reduce the amount of double stopping for interfloor service.

Another object is to eliminate as many unnecessary stops of the elevator cars as possible to thereby relieve the demands on the elevator system.

A further object is to so control the operation of the hall calls and the car calls for theintermediate floors as to confin the service at those particular floors to only cars already scheduled by operated car buttons to make stops thereat.

It is also an object of my invention to provide apparatus for reducing the number of stops made by cars at intermediate fioors which may be easily and economically installed, operated and maintained in operation.

For a better understanding of my invention, reference may be had to the accompanying drawings, in which:

Figure 1 is a diagrammatic representation of an elevator system embodying two cars to be operated in accordance with my invention;

Fig. 2 represents the arrangement of the contact segments and contact brushes on one of the fioor selectors included in Fig. 1;

Figs. 3 and 4 collectively constitute a diagrammatic representation, in the straight line style, of the signal and control system for the two cars illustrated in Fig. 1; and

Figs. 3A and 4A collectively constitute an explanatory illustration of the relays embodied in Figs. 3 and 4, in which the coils and contact members of the relays are disposed in horizontal alignment with their positions in the straight line circuits of Figs. 3 and 4, so that the reader may readily determine the identification of any relay, the number and kind of its contact members, and the position of its coil in the straight line circuits. For convenience in reading the drawings, Fig. 4 should be placed under Fig. 3, and Fig. 3A should be placed beside Fig. 3 with Fig. 4A underneath it.

The main relays included in the system are designated as follows:

Relays individual to car A U=up direction switch D=down direction switch W=up direction preference relay X=down direction preference relay M=car running relay V=high-speed relay C=fioor stop buttons in car CC=holding coils for buttons in car S=hall button stopping relay T=car button stopping relay TE=car holding and timing relay E=inductor relay for decelerating car F=inductor relay for stopping car G=re1ay for holding inductor relays energized while stopping Common to all cars 2UA=up car-selecting relay second floor 2DA:down car-selecting relay second fioor 2UR=up call-storing relays at second floor 2DR=down call-storing relays at second floor 2UJ=up hall button at second floor 2DJ=down hall button at second fioor The control system is illustrated in connection with two cars A and B provided for serving five fioors, but it is to be understood that the invention may be used in connection with any number of cars serving any number of fioors.

The relays for car B are given the same designation as those for car A with the letter B prefixed thereto. The letters U and D indicate up and down direction. The prefix numerals indicate the floor, and the sufiix numerals indicate the contact members of the relays.

Referring more particularly to the drawings, the car A is indicated as suitably suspended by a cable I I which passes over a hoisting drum l3 to a counterweight l5.

Referring to the control system for car A as shown in Figs. 3 and 4, the hoisting drum [3 is directly coupled by a shaft I! to an armature 13 of a suitable hoisting motor IS, the field winding 20 of which is connected for constant voltage energization to a source of energy designated by the supply conductors L+l and Ll.

A variable voltage system of control is provided for operating the hoisting motor l9, wherein the armature I8 is connected in a closed circuit 2! with the armature 22 of a generator 23. The generator is provided with a separately excited field winding 24 and a cumulative series field winding 25. A resistor H is connected in the circuit of the field winding 24 for controlling the output of the generator. The generator armature 22 may be operated by any suitable constant speed driving motor (not shown).

A brake 26 operated by an electromagnet is provided for applying a braking eifect to the hoistin drum when the car is brought to a stop, the brake magnet being energized to release the brake when the car is running and being deengized to apply the brake when the supply of power to the car is out off.

The direction and speed of the hoisting motor l9 may be suitably controlled by controlling the direction and value of the excitation current supplied to the separately excited field winding 24.

The direction of excitation current for the field Winding may be suitably controlled by an up direction switch U and a down direction switch D. The value of the current supplied may be controlled by means of a high-speed relay V for connecting and disconnecting the resistor TI in the circuit of the generator field winding.

The doors and gates of the elevator car A are provided with safety devices 28, so that all the doors and car gates (not shown) must be closed before the car can be operated.

In the present system, the car is started by the act of closing the doors and the car gate. When the corridor door and the car gate are closed the car will start operating in the direction for which its control apparatus is set at the time.

Any suitable system may be employed for automatically stopping the car at the floors it serves. As one example ofsuch a system, I have illustrated an automatic inductor relay landing system similar to that disclosed in Patent No. 1,884,446, issued October 25, 1932, to K. N. White and G. H. Hearn.

The landing system for car A includes a highspeed decelerating inductor relay E and a stopping inductor relay F for causing the car to be automatically decelerated from its high speed and brought to a stop exactly level with any floor it approaches for which a stop button has been operated. The inductor relay E is mounted on the car in position to cooperate with an inductor plate UE for the up direction and an inductor plate DE for the down direction. The inductor relay F cooperates with th inductor plate UF for the up direction and an inductor plate DF for the down direction. The inducto plates are constructed of magnetic material and are mounted in the hatchWay in position to cooperate with and open contact members on the inductor relays when the relays are in an energized condition as the car approaches the floor at which it is to stop. Only the inductor plates for one floor have been shown, but a similar set may be provided for each floor.

The inductor relay E is provided with up contact members El and down contact members E2 which are opened by the inductor plates DE and UE to decelerate the car. Stopping contacts FI and F2 on inductor relay F are disposed to be opened by the up inductor plate UP and the down inductor plate DF in stopping the car level with the floor.

An inductor maintaining relay G is provided for maintaining the inductor relays in energized condition after they are energized until the stop for which they are energized is completed.

The energization of the inductor relays on car A for decelerating and stopping that car at the various floors is effected either by a car button stopping relay T operated by the stop push buttons in the car or by a floor button stopping relay S operated by stop push buttons at the floor landings.

The stop push buttons 2C, 30 and 4C in the car comprise one for each of the intermediate floors. The pressing of a car button by the car attendant will register a stop call, or, in other words, initiate and maintain a circuit which will be completed by the arrival of the car within a predetermined distance of the floor corresponding to the button and thereby energize the stopping relay T which will, in turn, energize the inductor relays to stop the car at that floor. In this manner, the car may be stopped at any intermediate floor by pressing the push button in the car for that purpose.

The car buttons are provided with holding or registering coils 20C, 3G0 and 4C0 which operate to hold the buttons in a depressed position after they are pressed by the car attendant, thereby storing the calls until the car makes the stops.

The hall or floor push buttons are designated as IUJ, ZUJ, 3UJ, 4UJ for up direction and as 5DJ, lD'J, 3DJ and 2DJ for the down direction. The pressing of a floor button will initiate the storing of a stop call for the nearest approaching car for the corresponding direction. Although the car button are individual to each car, the floor buttons are common to both cars; that is, there is only one up button and one down button .at each intermediate floor regardless of the number of cars. Hence the waiting passenger at a floor has only one button to press to stop the first car for the direction in which he desires to go.

Associated with each floor push button is a stop call registering or storing relay. These relays are designated as IUR, ZUR, 3UR and 4UR for the up direction and 5BR, 4DR, 3DR and ZDR for the down direction and they operate to store or maintain the stop calls set up by the operated hall buttons until the calls are answered by the cars.

A cancellation coil is mounted upon each of the call registering relays for the purpose of deenergizing and restoring that relay when the call stored thereon is answered. The cancella tion coils for the up direction are IURN, ZURN, 3URN and 4URN, while the coils for the down direction are 5DRN, 4DRN, 3DRN and ZDRN.

A stopping circuit is associated with each call registerin relay for an intermediate floor. The operation or" call registering relay will cause the stopping circuit associated with it to be energized for operating the stopping relay T of the .nearest approaching car for the corresponding direction to caus it tostop at that floor in answer to the stored call for that floor. The stopping circuits are designated as ZUS, 3US and 4US for the up direction and as (IDS, 3DS and ZDS for the down direction.

A plurality of up car selecting relays and a plurality of down car selecting relays are provided for so controlling the stopping circuits operated by the hall buttons as to eliminate useless stops of the cars at floors where hall call buttons have been operated and for which corresponding car buttons have been operated. The

up car selectin relays are designated as ZUA, 3UA and 4UA and those for the down direction as ZDA, 3DA and 4DA.

A car running relay M is also provided for conditioning certain circuits in a predetermined manner when the car is in operation.

A car holding and timing relay TE controlled by the car running relay M is provided for preventing operation of the direction switches U or D for a, predetermined time after the car arrives and stops at a landing. The relay TE is provided with an opening time delay to cause it to open slowly after it has been deenergized, so that its back contacts will not be reclosed until the expiration of the predetermined period of time after the relay is deenergized. This relay TE prevents the car from restarting quickly as soon as it stops at a floor landing, and thus gives the car attendant time to open the doors. Once the doors are open, the car will not restart until the doors are closed.

An up direction preference relay W and a down direction preference relay X are provided for car A to cause it to continue operation in th direction in which it starts. A top limit switch LT and a bottom limit switch LB are provided for reversing the direction switches when the car arrives at its upper or its lower terminal.

A floor selecter SE is provided for each car for connecting the circuits for the push buttons, relays, etc., in accordance with the position of the car with respect to the floors served. The floor selector has a plurality of stationary contact segments, as shown in Fig. 2, arranged according to the floors and disposed to be engaged by cooperating contact brushes 30, 3| and 32 for the up direction and 40, 4|, and 42 for the down direction. The brushes are mounted upon and insulated from a suitable arm SM. The movable arm is operated in accordance with the movements of the car by means of a screw shaft 56 and a gear 58 driven by some part of the operating mechanism of the car such as the shaft 51. The operation of the shaft 56 moves the arm SM up and down over the stationary contact segments. The arm SM is also provided with a cam 50 which engages sequentiallythe restoring switches M, 71.3 and M for the button holding coils 20C, 3C0 and 4C0. As the selector arm moves up and down, it opens the restoring switch for the floor at which the car is located,

so that when a car stops at a floor, the holding coil for that floor is deenergized to cancel and release its car button if it has been operated for a stop. The coils and buttons operate for both up and down direction.

The selector arm engages both up and down contact segments when moving from its lower terminal position to its upper terminal position, but the circuits connected to the brushes are controlled by the direction preference relays W and X in such manner that when the car is going down, only the down brushes are electrically connected to their circuits while the up brushes are disconnected from their circuits.

The group of contact segments a2, a3, and a4 under up-brush 30 are provided for completing circuits for energizing the hall stopping relay T. The up contact segments b2, b3, b4 and 125 under brush 33 are provided for energizing the car button stopping relay S. The contact segments dl, d2, d3, d4 and d under brush 32 are provided for canceling up calls registered on the up hall call registering relays. The contact segments (15, etc. under brush 40 are provided for canceling or restoring the down hall call relays. The contact segments fl, f2, f3 and f4 under brush 4| are provided for energizing the hall call stoppin relay S on down operation. The contact segments g2, g3 and g4 under brush 42 are provided for energizing the car button stopping relay T on down direction operation. The

lengths of the contact segments and the sizes of the brushes as well as their positions will vary in accordance with the difference in the height of floor, speed of cars, etc. Any suitable floor selector, of which there are many different kinds, may be substituted for the one shown in connection with the present system.

It is believed that the invention may be more clearly understood by assuming an operation of the system. It will be assumed that the supply conductors L+I and L-I, etc. are energized, that cars A and B are standing at the lower termina1 with their doors open, and that waiting passengers at the third floor and at the fourth floor press the up call buttons 3UJ and 4UJ at those floors to cause the next car for the up direction to stop for them. The pressing of the button 4UJ energizes the up direction call registering relay 4UR for the fourth floor by the circuit L+3, 4UJ, 4UR, 55, L3

The energized relay 4UR closes its contacts 4UR| and 4UR2. The closin of the contacts 4UR2 completes a self-holding circuit for the relay 4UR so that it will be maintained in energized condition until its restoring coil 4URN is energized to cancel the call thereon. The closing of the contacts 4UR! energizes the stopping circuit 4US leading to the stopping contact segments b4 and IBM for stopping the first .car to approach in the up direction.

The pressing of the hall call button 3UJ energizes the call registering relay 3 31?. for the third floor by the circuit 11-1-3, 3UJ, 3UR, 55, L3

The energized relay 3UR closes its contacts 3URI and 313532. The closing of the contacts 3UR2 completes a self-holding circuit of the relay to hold it in an energized condition until a car stops in the up direction at the third floor. The closed contacts 3URI energize the stopping circuit 3US leading to the contact segments b3 and Bb3 for stopping the first approaching car in the up direction.

Assume now that a passenger enters car A at the bottom terminal and requests the attendant to let him off at the fourth floor. Thereupon the attendant closes the door to start the car and presses the fourth floor car button 40 to cause the car to stop when it arrives at the fourth floor. The pressed button 40 is held in its depressed position by its holding coil 400 which is energized. by the circuit L+3, 400, I24, L3

The closed position of the button 40 closes its contacts 4Cl and 402. The closing of the contacts 4CI energizes the up contact segment a l so that the stopping relay T of car A will be energized to stop that car at the fourth floor when it arrives thereat. The closing of the contacts 4C2 energizes the car selecting relay 4UA by the circuit L+3, 4C2, W6, 4UA, L-4

The energized relay 4UA opens its back contacts 4UAI in the energized stopping circuit QUS leading to the contact segments b i and BM. Therefore, no up car will be stopped at the fourth floor by the present energized condition of the call storing relay AUR for the fourth floor. How-- ever, the car A is now scheduled to stop at the fourth fioor to let on" a car passenger, and, in so doing, can take on the waiting passenger who pressed the up button GUJ at that floor.

When the car attendant closed the door in car A while it was at the first floor, he closed the safety contacts 28 associated therewith thereby energizing the up direction switch U and the car running relay M by the circuit L-f-l, 'IEll, W'l, Fl, U, M, 28, L-I

The energized switch U closed its contacts UI, U2, U3, U4 and U5 and opened its contacts U5. The closed contacts U! energized the brake coil 26 by the circuit L+l, 25, UI, L|

and thereby released the brake to permit movement of the car. The closing of the contacts U2 and U3 energized the field winding 24 of the generator 23 by the circuit L+l, U2, 24,113, Tl, n

L+l, U4, El, V, L-l

to close its contacts VI and short-circuit the resistor r! in the circuit of the generator field winding to cause the car to move at its normal high speed.

The energized relay M closes its contacts. Ml, M2 and M3 and opens its back contacts M4. The closing of the contacts Ml connects the circuit for the up switch U and the relay M to the conductor L+ I, so that when the contacts TEI open, the relays U and M will remain energized. The closing of the contacts M2 prepares the circuit of the inductor relays for operation. The closing of the contacts M3 energizes the relay TE by the circuit L+l, M3, TEI, L-I

Car A is now moving upwardly toward the third floor at which the hall stop button has been operated, and, as it approaches that floor, its up brush 3| engages the contact segment b3 on its floor selector and thereby energizes its stopping relay S to cause it to stop at the third fioor. This circuit extends from L+l, 3URI, 3UAI, b3, 3!, W3, S, L-l

The energized stopping relay S closes its contacts SI thereby energizing the inductor relay E by the circuit n+2, SI, E, M2, L-I

This circuit also energizes the inductor holding relay G because that relay is in parallel with the inductor relay E. The holding relay G closes its contacts GI thereby providing a selfholding circuit for the inductor relays El and F. As the car approaches the third floor, it carries the inductor relay past the up inductor plate UE which causes the contacts El to open, thereby deenergizing the high speed relay V which, in turn, opens its contacts VI and thus reinserts the resistor rl in the circuit of the field winding 24 thereby decelerating the car from its. normal high speed to its normal landing speed.

The deenergized relay V also closes its back contacts V2, thereby energizing the inductor relay F. As the car approaches still more closely to the third floor, it moves the energized inductor relay F opposite the up stopping inductor plate UF which causes the contacts Fl to open, thereby deenergizing the up direction switch U and the car running relay M. The deenergized up switch U opens its contacts U2 and U3 in the generator field winding circuit, thereby deenergizing that circuit to out 01f the supply of energy to the hoisting motor l9, and opens its contacts Ul, thus deenergizing the brake coil 26 and applying the brake to stop and hold the car at the third floor. Car A is now stopped at the third floor and the attendant opens the door and car gate (not shown) and takes on the up passenger at that floor.

The deenergized relay M opens its contacts Ml, M2 and M3. The opening of the contacts Ml opens one circuit to the direction switches, and inasmuch as the contacts TEI are still open, the direction switches cannot now be energized to restart the car. The opening of the contacts M2 restores the inductor relays to their deenergized condition. The opening of the contacts M3 deenergizes the time delay relay TE which, after the expiration of a predetermined period of time, recloses its back contacts TEI in the circuit leading to the direction switches so that the car can now be restarted at any time by reclosing the door and gate.

The arrival of the car A at the third floor also caused its selector brush 32 to engage the up contact segment d3, thus energizing the restoring coil 3URN by the circuit L+3, 3UR2, 3URN, d3, W5, M4, L 3

The energized coil 3URN neutralizes the relay coil 3UR and thereby restores that relay to its normal condition, thus cancelling the up stop call on the hall button at the third floor.

While car A is moving upward and answering the stop call registered on the hall button at the third floor, it will be assumed that the attendant in car B starts to move that car to the upper terminal. Assuming that the attendant in car B closes the door, that car starts upwardly in the same manner as car A, and as it approaches the fourth floor, its up stopping brush B3! engages its up stopping contact Bb4 at the fourth floor. However, even though car B is the first car to approach the fourth floor in the up direction after the registering of the up stop call on the hall button thereat, it will not be stopped at that floor because the operation of the car button 40 in car A energized the car selecting relay 4UA which opened its contacts 4UA| in the stopping circuit leading to the contact segments b4 and BM thereby preventing them from stopping any car. Thus car B fails to stop at the fourth floor and moves on up to the upper terminal where it may be stopped by the usual limit switches (not shown) Returning now to car A, it will be assumed that that car completes its stop at the third floor, and that the attendant closes the door and car gate, thus closing the safety switches 28 to energize the up direction switch U and the car running relay M, as previously described. This causes car A to move on up its hatchway and as it approaches the fourth floor its up brush 30 engages the up stopping segment (14 and thereby energizes the stopping relay T of car A by the circuit L+3, 40!, a4, 3i W4, T, L-3

The energized relay J. closes its contacts Tl, thereby energizing the inductor relay E by the circuit L+I, Tl, E, M2, L-l

As car A approaches still closer to the fourth floor, it moves the inductor relay E past the up inductor plate UE for that floor. This causes the inductor relay to open its contacts El, thus deenergizing the high speed relay V to reinsert the resistor T1 in the generator field winding circuit to decelerate the car from its normal high speed to its normal stopping speed. As car A moves into stopping position for the fourth floor at stopping speed, the energized inductor relay F comes opposite the up inductor plate UP for the fourth floor, and is thereby operated to open its contacts Fl, thus deenergizing the up direction switch U and the car running relay M to stop the car as previously described in connection with the third floor stop.

Car A is now stopped at the fourth fioor by the operation of its car button to let off the passenger who boarded the car at the bottom terminal and for whom the attendant operated the car button 4E. In making this stop, the car also serves the waiting passenger at the fourth floor who pressed the up button 4UJ at that floor to stop an up car thereat.

By this operation it will be observed that my improved system will prevent the unnecessary stopping of more than one car at a floor to take on a passenger at that fioor when a car button has already been operated to let off a passenger at that floor.

It will also be apparent from the operation of this system that a registered call for a floor ren ders an earlier or a later registered fioor call for the same floor and direction ineffective to stop an of th cars and therefore that the only time when two cars will stop at a floor will be when a stop button in each car is operated; that is, each car will be carrying a passenger who desires to get ofi at the same floor. It makes no difierence Whether the hall call is registered before or after the car call; under either condition only the car with the operated car button will make the stop. From the foregoing it will be apparent that I have provided for a system in which the number of stop calls for interfioor service will be much terminal and a lower terminal, a starting and a stopping means for each car, an up hall switch and a down hall switch at each floor, a call registering device for each hall switch, and con nected for operation thereby, a stopping circuit for each call registering device, means responsive to operation of a call registering device for a fioor for energizing the stopping circuit corresponding thereto to operate the stopping means of the nearest approaching car in the corresponding direction to stop it at that floor, a selecting means associated with each stopping circuit, a plurality of car stopping switches in each car, one for each floor, means responsive to operation of a car switch for a floor ahead of the car and the approach of that car to that floor for operating the stopping means of that car to stop it thereat, means responsive to operation of a car switch to stop a car at a floor for operating the selecting means for the direction of operation of the car and the floor for which the car switch has been operated, and means responsive to operation of a selecting means for rendering the stopping circuit associated With it ineffective to stop any car.

2. In an elevator system, a plurality of cars for serving a plurality of floors, an up hall means and a down hall means foreach fioor for stopping the nearest approaching car in the corresponding direction, said hall means being common to all the cars, an up selecting device and a down selecting device for each floor, said selecting devices being common to all the cars, a plurality of car stopping switches in each car one for each floor for stopping that car at selected floors, means responsive to operation of a car switch fora floor ahead of its car for operating the selecting device for that fioor for the direction of operation of that car, and means responsive to operation of a selecting device for rendering the hall means for the corresponding floor and direction ineifective.

3. In an elevator system, a plurality of cars for serving a plurality of floors, means for starting the cars, an up hall means and a down hall means for each floor common to all the cars for storing stop calls, a plurality of car uttons in each car one for each floor for storing stop calls, a first stopping means associated with each car and responsive to an operated hall means for a fioor for stopping that car at that fioor, a second stopping means associated with each car and responsive to an operated car switch in that car for stopping it at the corresponding floor, an up car selecting device and a down car selecting device for each floor common to all the cars, means responsive to operation of a car switch for a floor ahead of its car for operating the selecting device for the same iioor and direction of operation, and means responsive to operation of a selecting device for preventing the hall means for the same ,fioor and the same direction of operation from operating the first stopping means of any car. HAROLD W. WILLIAMS. 

